The Phosphaturic Mesenchymal Tumor: Why is Definitive Diagnosis and Curative Surgery Often Delayed?

Abstract

Background Tumor-induced osteomalacia is a paraneoplastic syndrome resulting in renal phosphate wasting and decreased bone mineralization. Phosphaturic mesenchymal tumors represent a rare etiology of tumor-induced osteomalacia. Nonspecific symptoms of fatigue, bone pain, and musculoskeletal weakness make the diagnosis elusive and lead to a delay in surgical treatment. Questions/purposes In this case series, the following three questions were asked: (1) How do the clinical presentation and features of phosphaturic mesenchymal tumors delay the diagnosis? (2) What is the clinical course after surgical treatment of phosphaturic mesenchymal tumors? (3) How frequently do phosphaturic mesenchymal tumors recur and are there factors associated with recurrence?Methods This study retrospectively reviewed the cases of five adults diagnosed and treated for phosphaturic mesenchymal tumors. Patients were identified through an internal orthopaedic oncology database with clinical, surgical, and histologic data obtained through a systematic chart review. Results Five patients presented with a long-standing history of osteomalacia, generalized fatigue, pain, and weakness before the diagnosis was reached at an average of 7.2 years (range, 2-12 years) after initial symptom onset. The diagnosis appeared to be delayed owing to the cryptic medical presentation, difficulty in locating tumor by imaging, and confirming histologic appearance. Two patients treated with wide surgical resection did not experience recurrence compared with three patients who did show recurrent signs and symptoms after marginal excision. A postoperative increase in fibroblast-derived growth factor-23 was associated with recurrent disease. Conclusions Although uncommon, the diagnosis of phosphaturic mesenchymal tumor should be considered in any patient who presents with hypophosphaturic osteomalacia and no other physiologic cause. Definitive treatment is early, wide surgical resection. Level of Evidence Level IV, therapeutic study. See the Instructions for Authors for a complete description of levels of evidence.

The diagnostic dilemma of tumor induced osteomalacia: a retrospective analysis of 144 cases

“…Moreover, our data revealed that the definite diagnosis and effective treatment of TIO was significantly delayed for years. Our data are consistent with repeated reports of delays in diagnosis, improper treatment and prolonged morbidity of TIO patients [8][9][10][11][12][13]18]. A typical example is a case report from E. Michael Lewiecki and his colleague, describing an unusual TIO case presented with musculoskeletal symptoms and fragility fractures [13].…”

“…Nevertheless, missed diagnoses or even misdiagnoses with subsequently diagnostic and therapeutic delay (ranging from 3-19 years) are commonly seen in reported cases of TIO, accompanied by prolonged morbidity and poor prognosis [8][9][10][11][12][13]. This reflects the relatively poor recognition of the rare disease among physicians.…”

Phosphaturic Mesenchymal Tumor: 2 New Oral Cases and Review of 53 Cases in the Head and Neck

“…Phosphaturic mesenchymal tumor (PMT) is a rare mesenchymal neoplasm with unpredictable biological behavior that has been associated with oncogenic osteomalacia (OO) [1][2][3]. It is a paraneoplastic syndrome that is considered to be an acquired type of osteomalacia and is caused by a variety of mesenchymal neoplasms [4,5].…”

Sinonasal Tumour causing Osteomalacia. A case report

“…As a result there is usually a delay in diagnosis, as long as 15 years has been reported 8 . Moreover the initial presentation is usually vague and medical presentation instead of anatomical 9 . There are various modalities for tumour localization such as routine radiographs, ultrasonography, CECT, magnetic resonance imaging (MRI), whole body technetium scan and octreotide scintigraphy 10,11 .…”